The invention is based on a priority application EP 01 440 297.8 which is hereby incorporated by reference.
The present invention relates to a method for the testing and commissioning of an electrical circuit unit (integrated circuit, module, device), in which method test signals are exchanged, via an electrical test interface provided for the purposes, between the environment of the circuit unit and a test circuit unit contained in the said circuit unit, in which method tests are carried out by the test circuit unit within the circuit unit, the said tests being initiated externally by test signals and the results of the tests being transmitted externally via test signals, an electrical circuit unit (integrated circuit, module, device) with a test circuit unit contained in the circuit unit and an electrical test interface that is designed so that, via the latter, test signals can be exchanged between the environment of the circuit unit and the test circuit unit contained in the circuit unit, in which circuit unit the test circuit unit is designed so that, by means of the latter, tests can be carried out within the circuit unit, the said tests being able to be initiated externally by test signals and the results of the tests being able to be transmitted externally via test signals, and an electrical circuit unit (integrated circuit, module, device) that is designed at least partially as an electrically reconfigurable circuit.
The fact that a newly manufactured circuit can also be checked (tested) before it is commissioned or used may be regarded as obvious. It has also been known for a long time that the tests are automated in industrial production. Apart from test pins (probes), by means of which test signals can be applied or test results can be tapped, the use of integrated test circuits has also been known for a long time. The term “integrated” is in this context not understood to denote a specific technology, but rather that such an integrated test circuit is an integral component of the respective circuit and is manufactured in conjunction with the latter and also remains connected to the latter after the tests.
The above comments apply irrespective of whether the “circuit” is now an integrated circuit in the contemporary stricter sense, or is a module with possibly several integrated circuits or even a larger device that in turn possibly consists of several modules. All this is intended to be included in the generic term “electrical circuit unit” used here. Also, the test circuit, like the circuit unit itself, is depending on the circumstances constructed in a hierarchical manner and may in the case of a relatively large device altogether comprise a complete test module, an integrated circuit as test circuit in each individual module, and a “test corner” in each individual integrated circuit. Suitable signal pathways are then necessarily also present on the one hand between these test circuits and on the other hand starting from these test circuits and passing through the circuit parts to be tested and back again to the test circuits. It is also necessarily possible to initiate the tests externally by test signals and also to transmit the results externally via test signals. To cover such complex arrangements there is an IEEE Norm, namely IEEE 1149.1, “IEEE Standard Test Access Port and Boundary Scan Architecture”, as well as subsidiary norms for more detailed specific application cases.
It is of course in principle also possible to carry out such tests subsequently from time to time during operation, via such integrated test circuits. As a rule though this facility is not provided since these test circuits constitute an unnecessary ballast that merely takes up space and, since they cannot be completely disconnected, possibly even consume unnecessary energy and produce corresponding heat.